外周血循环肿瘤细胞在晚期肺癌患者的预测及预后价值研究

Circulating tumor cells as a prognostic and predictive indicator in advanced lung cancer patients

目的应用免疫磁珠阴性富集技术结合荧光细胞化学染色方法,检测肺癌患者外周静脉血中循环肿瘤细胞(CTC)的敏感性及特异性;分析肺癌患者CTC水平与临床疗效的相关性。方法 2007年7月～2008年4月在北京协和医院呼吸内科肺癌中心诊断的144例肺癌患者作为研究对象,并设健康对照组35例、良性肺疾病组28例。采集上述各组静脉血标本,应用免疫磁珠阴性富集分离及免疫荧光细胞化学染色方法检测静脉血中CK18^+/CD45^-/CTC计数,凡≥1判定为阳性。随访上述52例入院化疗患者治疗后CTC,与其临床疗效、生存进行相关性分析。结果健康和良性肺疾病组CTC检测阳性分别为2例(5.71%)及1例(3.57%),肺癌组未接受抗肿瘤治疗前CTC的阳性率64.5%(93/144)。其中Ⅲ_A、Ⅲ_B及Ⅳ期分别为32.0%、56.8%及78.0%。腺癌、鳞癌、小细胞癌CTC阳性率分别为66.7%、70%及62%。52例肺癌患者进行每周期化疗后CTC检测,疗前CTC阳性率69.2%(36/52),3个周期化疗后下降至6.5%(3/46),显示CTC与疗效相关。结论本检测方法简便,敏感性为93.1%,特异性为72.8%;CTC阳性率与疾病分期、吸烟、疗效及转移相关,CTC水平越高可能提示预后不良。

Objective To explore the clinical value of circulating tumor cells （CTCs） in prognosis and in assessing the treatment effectivene for patients with lung cancer. Methods In a prospective, single-center and small sampling study, the levels of CTC was determined at baseline in 144 patients with emerging or recurrent lung cancer and followed 52 patients with CTC numbers after each cycle of chemotherapy. We then performed correlation analysis between CTC variation and treatment-response was perforated based on RECIST criteria. Using cancer cell isolating technology, an immu- nomagnetic beads-based rare cell enrichment system using leukocyte depletion mechanism, we counted the identified CK18 ＋/CD45 - CTCs in 7.5ml venous blood of the lung cancer patients under fluorescence microscopy. Results Totally 144 blood samples were collected from newly diagnosed or recurrent lung cancer patients who had been treatment-naYve. Benign respiratory diseases including tuberculosis （ n = 28） and healthy control samples （ n = 35） were collected during the same study period. The technology was easy to manage and repeatable, with a sensitivity of 93.1% and specificity of 72. 80/o in lung cancer patients. The patients with TNM stage m A had a CTC positive rate of 32. 0% （8/25） , and those of Ⅲ B 56. 8% （21/37） and Ⅳ 78.0% （64/82） （P 〈0. 01 ）. Fifty two patients were followed up with CTC after each cycle of chemotherapy for less than 6 cycles. After three cycles of chemotherapy, CTC positive rate fell from 69.2% （36/52） to 6. 5% （3/46）. Correlation analysis showed the variation of post-cycle 1 CTC was coincident with RECIST criteria by CT scan after two cycles of chemotherapy. Conclusion The above-mentioned method is highly sensitive and specific in detecting CTC of patients with advanced lung cancer. CTC is closely related to the metastasis status of the tmnor. The initial level of CTC and right after the therapy identified using this method has strong prognostic value. The variation of CTC in the course of chemotherapy may be a useful indicator of the chemo-response or disease-progression.